2.4 BP Brake IN

**Little boat that could** · 05-01-2025, 10:32 PM

Just wondering what oil is good for brake in. I found Pennzoil Premium Outboard & Multi-Purpose 2-Cycle i believe it's nonsynthetic. The mototrs are all nic cylinders and coated rings Thank you

**XstreamVking** · 05-02-2025, 09:45 AM

Jay Smith (Look him up, a very good engine builder) said for nic, engines he used the blue merc oil (non syn) Then went to full syn after break in. 32-1 ratio Maybe someone else will chime in and back this up? Back when I had a BP all we had was the orig blue merc oil, Which is what I ran at 32-1.

**David - WI** · 05-02-2025, 11:28 AM

Aren't BP cylinders chrome? Have to be careful choosing rings.

**XstreamVking** · 05-02-2025, 11:43 AM

David, now that you mention it they were chrome bores. Got curious and googled it. 25-1 for break in and just references a TCW-3 oil?

**David - WI** · 05-02-2025, 12:51 PM

I don't remember it all, but I know you can't run chrome rings in a chrome bore.

**Carter Powell** · 05-02-2025, 01:26 PM

Your motor could be chrome or nikasil. I had two of these and they were both nikasil. Some of the oval port motors were chrome. Carter

**tlwjkw** · 05-02-2025, 05:29 PM

think they were chrome till '89.. 90's went ta nic along with most of tha replacement blocks...

**skialot2** · 05-02-2025, 05:59 PM

I don't remember what year it was but my Bridgeport had nicasil bores. I always used a special Mercury racing 2 cycle oil. I was told not to use the regular oil. I cannot find even a trace of it online anymore. I believe it was red. I ran it at 35 :1. I blew it up 3 times but I never had a piston problem. All 3 times it broke a rod bolt.

**Little boat that could** · 05-02-2025, 08:19 PM

Later years were all nic. I have a pair of Mod VP they are all chrome

**108** · 05-03-2025, 05:12 AM

Pennzoil premium plus @ 32:1

**25two.stroke** · 05-05-2025, 06:10 PM

Pennzoil premium plus - 32:1

Merc still makes the red racing oil that is thin in viscosity. Almost $100/gallon now...I aint paying that when the $21/gal XLF has never done me wrong.

**skialot2** · 05-05-2025, 07:54 PM

Originally Posted by 25two.stroke

Pennzoil premium plus - 32:1

Merc still makes the red racing oil that is thin in viscosity. Almost $100/gallon now...I aint paying that when the $21/gal XLF has never done me wrong.

Yep. It wasn't cheap back then either. I think it was $85 for 2 1/2 gallons while the regular oil was less than $10 a gallon.